Lithium
Lithium was discovered in the 1800's by a Brazilian scientist Jose Bonifacio de Andrade e Silva, who found the element in a Swedish mine. 18 years later the element was formally found by August Arfwedson who found the element in the ore he was testing. This element seemed to make compounds like potassium and sodium. It was given the greek name λιθoς(lithos) which means stone but that soon adapted to lithium. Scientists tried and failed to separate lithium from lithium salt. Finally in 1821 William Thomos Brande was able to separate lithium using electrolysis.